display a list of names(when we press first letter)

import javax.swing.*;
class Name
{ 
    public static void main (String arg[])
    {

        String st=JOptionPane.showInputDialog(null,"Enter any character");
        char ch=st.charAt(0);
        switch(ch)
        {
            case 'A': JOptionPane.showMessageDialog(null,"Ali\n Azam\n Afzal\n");
            break;
            case 'B': JOptionPane.showMessageDialog(null,"Babar\n Bebo\n Bell\n");
            break;
            default: 
                JOptionPane.showMessageDialog(null,"Invalid");
        } 
     } 
}

import java.util.*;

class DisplaySetOfNames{
    public static void main(String[] args) 
    {
        String[] countries = {"Afghanistan", "Albania", "Algeria", "Andorra", "Angola","Argentina"
,"Armenia","Austria","Bahamas","Bahrain", "Bangladesh","Barbados", "Belarus","Belgium",
"Benin","Bhutan","Bolivia","Bosnia & Herzegovina","Botswana","Brazil","Bulgaria",
"Burkina Faso","Burma","Burundi","Cambodia","Cameroon","Canada", "China","Colombia",
"Comoros","Congo","Croatia","Cuba","Cyprus","Czech Republic","Denmark", "Georgia",
"Germany","Ghana","Great Britain","Greece","Hungary","Holland","India","Iran","Iraq",
"Italy","Somalia", "Spain", "Sri Lanka", "Sudan","Suriname", "Swaziland","Sweden",
"Switzerland", "Syria","Uganda","Ukraine","United Arab Emirates","United Kingdom",
"United States","Uruguay","Uzbekistan","Vanuatu","Venezuela","Vietnam",
"Yemen","Zaire","Zambia","Zimbabwe"};
        Scanner input=new Scanner(System.in);
        System.out.print("Enter letter: ");
        String letter=input.next().substring(0,1);
        System.out.println();
        for(int i=0;i<countries.length;i++){
            if(countries[i].startsWith(letter)){
                System.out.println(countries[i]);
            }
        }
    }
}

import java.util.*;

class DisplaySetOfNames{
    public static void main(String[] args) 
    {
        String[] countries = {"Afghanistan", "Albania", "Algeria", "Andorra", "Angola","Argentina"
,"Armenia","Austria","Bahamas","Bahrain", "Bangladesh","Barbados", "Belarus","Belgium",
"Benin","Bhutan","Bolivia","Bosnia & Herzegovina","Botswana","Brazil","Bulgaria",
"Burkina Faso","Burma","Burundi","Cambodia","Cameroon","Canada", "China","Colombia",
"Comoros","Congo","Croatia","Cuba","Cyprus","Czech Republic","Denmark", "Georgia",
"Germany","Ghana","Great Britain","Greece","Hungary","Holland","India","Iran","Iraq",
"Italy","Somalia", "Spain", "Sri Lanka", "Sudan","Suriname", "Swaziland","Sweden",
"Switzerland", "Syria","Uganda","Ukraine","United Arab Emirates","United Kingdom",
"United States","Uruguay","Uzbekistan","Vanuatu","Venezuela","Vietnam",
"Yemen","Zaire","Zambia","Zimbabwe"};
        Scanner input=new Scanner(System.in);
        System.out.print("Enter letter: ");
        String letter=input.next().substring(0,1);
        System.out.println();
        for(int i=0;i<countries.length;i++){
            if(countries[i].startsWith(letter)){
                System.out.println(countries[i]);
            }
        }
    }
}